1. Field of the Invention
The invention relates to a printed circuit board and a method of manufacturing the printed circuit board.
2. Description of the Related Art
When rolled copper foils and electrolytic copper foils are used as wiring materials for printed circuit board, the copper surface is usually oxidized and this causes deterioration in bondability when semiconductor components, etc., are soldered to the wiring.
A method is known in which Ni is plated on a copper surface and Au is further plated thereon so as to suppress oxidation of copper surface and thereby to improve solder bondability or wire-bonding properties (see JP-A-2013-16558, paragraph 0008).
Meanwhile, for the purpose of improving corrosion resistance of copper or copper alloy members, there is a method in which zinc (Zn) is plated on a surface of copper material and is subsequently diffused by heat treatment to form a copper-zinc (Cu—Zn) layer with a zinc (Zn) concentration of 10 to 40% (see JP-A-562-040361).
Furthermore, in recent years, it was reported that amorphous alloys exhibit excellent corrosion resistance due to the structure in which atoms are densely packed (see WO2007/108496, JP-A-2008-045203, JP-A-2004-176082, JP-A-2001-059198 and JP-A-2010-163641).